# Biblatex. Two references under same name. When I changed the name I receive a character error

In my .bib file I have two references under the same reference name (not the authors' name. I guess there should be a professional term for the reference name). When I call that name out of the .bib file I receive an error where \printbibliography is located. The two references are:

@article{lopez2011cavitation,
title={Cavitation in elastomeric solids: I—A defect-growth theory},
author={Lopez-Pamies, Oscar and Idiart, Martin I and Nakamura, Toshio},
journal={Journal of the Mechanics and Physics of Solids},
volume={59},
number={8},
pages={1464--1487},
year={2011},
publisher={Elsevier}
}

@article{lopez2011cavitation,
title={Cavitation in elastomeric solids: II—Onset-of-cavitation surfaces for Neo-Hookean materials},
author={Lopez-Pamies, Oscar and Nakamura, Toshio and Idiart, Mart{\'\i}n I},
journal={Journal of the Mechanics and Physics of Solids},
volume={59},
number={8},
pages={1488--1505},
year={2011},
publisher={Elsevier}
}


How can I cite these two references that can be differentialble in the text. Any suggestion is appreciated.

MWE

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[backend=biber,style=chicago-authordate,]{biblatex}
\begin{document}
\renewcommand{\labelenumi}{\arabic{enumi}}
\begin{enumerate}
\item \cite{alopez2011cavitation}
\item \cite{blopez2011cavitation}
\end{enumerate}
\newpage
\printbibliography
\end{document}


And the content of TexStackExc.bib is

@article{alopez2011cavitation,
title={Cavitation in elastomeric solids: I—A defect-growth theory},
author={Lopez-Pamies, Oscar and Idiart, Martin I and Nakamura, Toshio},
journal={Journal of the Mechanics and Physics of Solids},
volume={59},
number={8},
pages={1464--1487},
year={2011},
publisher={Elsevier}
}

@article{blopez2011cavitation,
title={Cavitation in elastomeric solids: II—Onset-of-cavitation surfaces for Neo-Hookean materials},
author={Lopez-Pamies, Oscar and Nakamura, Toshio and Idiart, Martin I},
journal={Journal of the Mechanics and Physics of Solids},
volume={59},
number={8},
pages={1488--1505},
year={2011},
publisher={Elsevier}
}


The source of error was the author name, Mart{\'\i}n. I replaced {\'\i} with i and also deleted the temporary files and now it prints the bibliography with no error.

• You can't use the same key for two bib entries, change one of them. Dec 29 '17 at 17:54
• It would help you would mentioned which error you get. A complete example would be a good idea too. Dec 29 '17 at 17:58
• If I should guess: replace the \'\i with í in the bib-file. Dec 29 '17 at 18:04
• All the evidence points to the í being problematic here. I can compile your second MWE without a problem, but if I add in Mart{\'\i}n again, I get the error Error: Unicode char ́ (U+301) Dec 29 '17 at 18:21
• @UlrikeFischer Do you want to write an answer, or do we close this as a duplicate of tex.stackexchange.com/q/251261/35864? Dec 29 '17 at 18:33

  [252] Utils.pm:169> WARN - Duplicate entry key: 'lopez2011cavitation' in file 'test.bib', skipping ...

When you change the key names to avoid the duplicate the second entry is used too and the \'\i leads to an known error, see e.g. Input encoding error after upgrading from Biber 1.9 to Biber 2.1, or https://tex.stackexchange.com/a/268579/2388 (they are more similar questions).